function vistformfwd(tform, wdata, zdata, N)
    if nargin < 4
        N =10;
    end
    [w, z] = meshgrid(linspace(wdata(1), zdata(2), N), linspace(wdata(1), zdata(2), N));
    wz = [w(:) z(:)];
    xy = tformfwd([w(:) z(:)], tform);
    x = reshape(xy(:, 1), size(w));
    y = reshape(xy(:, 2), size(z));
    wx = [w(:); x(:)];
    wxlimits = [min(wx) max(wx)];
    zy = [z(:); y(:)];
    zylimits = [min(zy) max(zy)];
    
    subplot(1, 2, 1)
    plot(w, z, 'b'), axis equal, axis ij
    hold on
    plot(w', z', 'b')
    hold off
    xlim(wxlimits)
    ylim(zylimits)
    set(gca, 'XAxisLocation', 'top')
    xlabel('w'), ylabel('z')
    
    subplot(1, 2, 2)
    plot(x, y, 'b'), axis equal, axis ij
    hold on
    plot(x', y', 'b')
    hold off
    xlim(wxlimits)
    ylim(zylimits)
    set(gca, 'XAxisLocation', 'top')
    xlabel('x'), ylabel('y')
end
